■ Chennai to be developed as a ‘sponge city’ –
∆ To combat urban floods, it is necessary to use new water management systems and convert Chennai into a sponge city.
∆ The idea behind sponge cities is to make cities more permeable, with more open spaces to collect rainfall and enable it to sink into aquifers.
∆ The city’s Water Resources Department is considering the potential of drilling recharge holes in smaller water bodies.
● What is sponge city:
∆ Sponge city is a novel urban construction model that aims to improve flood control while also strengthening ecological infrastructure and drainage systems.
∆ In the year 2000, Chinese researchers suggested this hypothesis.
∆ In the last few decades of growing urbanisation, sponge city strategies have been used more frequently in new construction than in rehabilitated complexes.
∆ The Yanfang residential neighbourhood in Xiamen and Langang Park in Shanghai are two recent constructions that demonstrate this tendency.
● Need for sponge city in india:
∆ Flooding has been a common occurrence in Indian cities.
∆ In managing or reducing the recurrence of big floods in urban areas, India’s land policy has proved ineffective.
∆ Cities lack an adequate drainage system.
∆ Water is wasted due to concrete constructions in metropolitan areas.
● Important aspects of designing such systems:
∆ Protection: Focuses on the city’s original environmentally vulnerable regions, like rivers, lakes, and ditches. The water environment is progressively treated and the damaged urban ecology is restored using natural plants, soil, and microorganisms.
∆ Restoration: It includes identifying ecological patches, establishing ecological corridors, strengthening the linkages between the patches, forming a network, and outlining the blue and green lines to restore the aquatic biological environment.
∆ Mandatory Measures: To conserve ecological patches, maintain their storage capacity, increase source management, and develop ecological sponges of various scales, mandatory measures apply to urban roadways, urban green spaces, urban water systems, residential areas, and special structures.
● Advantages of a sponge city:
∆ This technology aids in the reduction of urban floods, the urban heat island effect, and the scarcity of water supplies.
∆ By absorbing and retaining rainwater and utilising it to decrease floods, it also benefits the ecology and wildlife.
∆ Sponge city policies are nature-based solutions that capture, store, and filter water using natural landscapes.
∆ This approach was inspired by an old understanding of climate adaptability, particularly in the monsoon area.
● Initiatives for Sponge city in India:
∆ The sponge city’s major goal is to make cities more permeable so that rainwater may be collected and used. initiatives like
∆ The National Heritage City Development & Augmentation Yojana (HRIDAY).
∆ The Atal Mission for Rejuvenation & Urban Transformation (AMRUT).
∆ The Smart Cities Mission, may efficiently deliver all of these.
